First off, we have a series of portals. These portals are topped by a crystal that looks very similar to the wind stones of Silithus, and in fact, each portal and crystal seems specifically marked to summon a specific element. There's also a bloodstained sacrificial altar and a couple of banners, all of these have a very specific dragon-like motif.
The Twilight's Hammer has already been confirmed to be working with Deathwing in Cataclysm, and since they're an elemental doomsday cult dedicated to bringing about the return of the Old Gods, busting Deathwing out of prison is right up their alley. We should probably expect to see these models in game relatively soon, and probably as part of a plot by the Twilight's Hammer to summon Deathwing back into the world -- a plot which will, of course, eventually succeed.
Stayed tuned for more coverage of Patch 3.3.3 and the Cataclysm opening event as it develops!
Gallery: Cataclysm models and doodads